What stays on your device.

Figures you type into a calculator stay in the page. Image tools read a file locally, redraw it, and offer a download. Those files are not uploaded.

Closing the tab clears the figures, unless your own browser has kept the page.

Light or dark mode is saved in local storage, under the name nb-theme. Tools you pin in the workspace are saved the same way, on this device. Clearing site data in the browser removes both.

The production site uses Vercel Web Analytics and Speed Insights. A page view and a performance measurement can be recorded when you visit the live site. Local development does not record those visits.

There is no account attached to a visit. Log in on this site is a preview. It does not create an account or store a password.

The note on the contact page is not sent or stored. It remains in the browser until you leave the page.

This page was last updated on 4 October 2026. If the way visits are recorded changes, this page will change with it.